How can I use calibration .csv data? about cam_lidar_calibration

[darrenjkt]

Are you referring to the calibration result from section 2.3.4 of the readme? With the csv titled "calibration_YYYY-MM-DD_HH-MM-SS.csv"? If so, just follow section 2.4 to get the final calibration parameters.

To go from roll, pitch, yaw, x, y, z to a transformation matrix, we first need to convert roll, pitch, yaw into a rotation matrix with rotation order XYZ.

Once you have the resulting 3x3 Rotation matrix from above, you can combine it with the, translation (x, y, z) in a single 4x4 homogenous transformation matrix T as shown below. This can be then used to convert points from camera to lidar frame.

There are different libraries for the above to help with rotation matrix/transformation like Eigen in C++ or scipy.spatial.transform.Rotation in python.

[jiyou384]

Thanks for your reply.

I'm studying the paper you linked and I have some questions.

I understood that you extract normal vectors by using RANSAC and calculate some errors on lidar coordinates.

However, I want to know how you extract vectors from camera coordinates and how can calculate roll, pitch, yaw, x, y, and z from them.